Transmission-gearing for hoists.



PATENTED APR. 14, 1908. A. J. THOMAS. TRANSMISSIONGEARING FOR HOISTS.

APPLICATION FILED MAR.1.1907.

UNITED STATES PATENT oFFIoE.

ARTHUR .T. THOMAS, OF HARVEY, ILLINOIS;

TRANSMISSION-(HEARING FOR HOIS'IS.

To all whom it may concern:

Be it known that'I, ARTHUR J. THOMAS, a citizen of the United States, residing at Han vey, county of (look, State of Illinois, have invented a certain new and useful improve ment in Transmission-Gearing for Hoists, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same, reference being had to the accompanying draw ings, which form a part of this specification.

My invention relates in general to hoisting apparatus and more particularly to transmission gearing for hoists.

Hoists for raising and lowering loads, such as those with which traveling cranes are provided, must be capable of readily elevating or lowering the load and of automatically sustaining the load at any desired height, as for instance while the load is being transported by the crane.

The primary object of my invention is to provide a hoist of the type above mentioned which will be simple and compact in construction, easily and positively operated, and convenient and efficient in use.

The embodiment of my invention herein disclosed may be generally described as comprising a rotary power shaft, a pair of pinions loosely mounted upon the power shaft, a clutch member surrounding and rotating with the power shaft intermediate of the pinion, clutch members on the pinions with one of which the first clutch member engages when the power shaft rotates on one direction, and with the other of which the first clutch member engages when the power shaft rotates in an opposite direction, a rotary hoisting shaft having fixed thereon a gear wheel meshing with one of said pinions, a second gear wheel meshing with the other pinion and having an interiorly screwthreaded hub engaged with a screw thread on the hoisting shaft, a friction disk surrounding and rotating with the hoisting shaft and adapted to engage a relatively stationary disk, a laterally pro ect1ng lug on the hub of said second gear wheeladapted to engage a stop carried by the hoisting shaft to limit the movement of the second gear wheel relatively to the hoisting shaft, and means for Specification of Letters Patent.

Application filed March 1, 1907.

Patented April 14;, 1908.

Serial No. 359,987.

transmitting motion from the hoisting shaft to a load which is to be raised, lowered, or held at a given elevation.

My invention will be more fully described hereinafter with reference to the accompanying drawing in which the same is illustrated as embodied in a convenient and practical form, and in which Figure l is a sectional view on line 11 Fig. 2; Fig. 2 a sectional view on line 22 Fig. 1; Fig. 3 a planview of the clutch and pinions removed from the power shaft; Fig. i a plan view of a modified form of clutch for alternately locking the pinions to the power shaft; and Fig. 5 a sectional view on line 55 Fig. 4,

The same reference characters are used to designate the same parts in the several figures of the drawing. a

Reference character A designates a rotary power shaft which may be driven by any suitable means not shown.

Reference characters B and B designate the two parts of a casing through which the power shaft extends. The two parts of the casing may be detachably secured together in any suitable manner, as by means of flanges through registering holes in which bolts I) extend. The lower part B of the casing may conveniently be provided with feet B, B by means of which the casing and hoisting mechanism contained therein may be secured to a support.

Fixed upon the power shaft A in any suitable manner as by means of a key 0 is a clutch member 0 having lugs c and 0 projecting laterally from the opposite sides thereof. Loosely surrounding the power shaft are pinions D and D located on the opposite sides of the clutch member and intermediate of the same and the bearings in the casing surrounding the power shaft. Lugs d and (1 project inwardly from and are fixed to the pinions D and D The lugs d and (Z are so located relatively to the lugs c andc on the clutch member that a rotation of the power shaft in the direction of the arrow will bring the lug a into engagement with the lug (1 while a rotation of the power shaft in an opposite direction will bring the lug 0 into engagement with the lug (i E designates a hoisting shaft which exhoisting shaft E as by means of a key 6.

The gear wheel E meshes with the pinion D. E designates a second gear wheel wlnch surrounds the hoisting shaft E and is provided with an interiorly screw-threaded hub i e engaging a screw-thread f on the hoisting shaft. The gear wheel E meshes with the pinion D F designates a collar clamped to the hoisting shaft E and provided with a lug f projecting laterally towards the hub of the gear wheel f designates a lug on the hub c of the gear wheel E which projects outwardly so as to engage the lugf when the gear wheel has moved axially a prer'letermined distance upon the shaft E.

G designates a disk surrounding the hoisting shaft and locked to rotate therewith in any suitable manner, as by means of grooves g in the disk engaging ribs 0 on the hub of the gear Wheel E. Located on opposite sides of the disk G are cooperating disks G and G which are locked against rotation in any suitable manner as by means of lugs' g, g projecting radially from their outer peripheries and engaging stops Z) on the inner surface of the upper part B of the casing and lugs I), b projecting inwardly from the lower part B of the casing. Fiber washers h are interposed between the adjacent surfaces of the friction disks G, G and G and also between the adjacent surfaces of gear wheels E and E and the adjacent surfaces of the friction disks G and G H indicates a gear wheel which may form part of a differential gearing for applying the rotary motion of the shaft E to a drum or other means (not shown) for raising or lowering a load.

The pinion D is provided with a sleeve (1 rotating therewith and extending around the shaft A to the outside of the casing. A fly wheel D is secured upon the outer end of the sleeve d.

The operation of my invention is as follows, when it is desired to rotate the hoisting shaft E in a direction to raise a load the power shaft is rotated in the direction of the arrow. The initial rotation of the shaft A in such direction brings the lug c on the clutch member C into contact with the lug cl on the pinion D so that the gear wheel E is rotated and therewith the shaft E in the direction of the arrow. hen the load is elevated to the desired height the rotation of the power shaft is discontinued. The load is held at such height by means of the friction disks which constitute a brake. A slight rotation of the shaft E by reason of the weight of the load in a direction opposite to that caused by the rotation of the shaft A in the direction of the arrow causes the rotation of the screw-thread f within the screwthreaded hub e of the gear wheel E to move the gear wheel E towards the gear wheel E thereby forcing the friction disks into close contact and locking the shaft to the stationary casing. The weight of the fly wheel D as well as the friction of the sleeve d and pinion D upon the shaft A prevent the gear wheel E from rotating with the hoisting shaft E when it is rotated by the load so that the shaft rotates within the hub of the gear wheel E and applies the brake.

Vfhen it is desired to lower the load the shaft A is rotated in an opposite direction to that indicated by the arrow which brings the lug c on the clutch member G into engagement with the lug (Z on the pinion D thereby rotating such pinion with the power shaft and communicating rotary motion to the gear wheel Such rotary motion of the gear wheel E moves the same axially away from the gear wheel E through the engagement of the screw-threads within its hub with the screw-thread on the shaft E. The weight of the load then rotates the shaft E in a direction to lower the load, the continued rotation of the gear wheel E by means of the pinion D permitting the shaft E to continue to rotate in a direction to lower the load owing to such rotation of the gear wheel E releasing the brake. The lowering of the load is, however, controlled by the rotation of the power shaft A as the rotation of the shaft E faster than the rotation of the gear wheel E causes the brake to be applied through the axial movement of the gear wheel E towards the friction disks owing to the engagement with a screw-thread on the shaft E with the screw-thread within the hub on the gear wheel When there is no load. supported by the hoisting shaft E-and it is desired to rotate such shaft in a direction to permit a load to be engaged, the power shaft A is rotated in a direction opposite to that indicated by the arrow, which through the rotation of the pinion D rotates the gear wheel E and moves the same axially upon the shaft E until the stop f on the hub of such gear wheel engages the lug f carried by the hoisting shaft. The continued rotation of the power shaft therefore positively rotates the hoisting shaft E in a direction to lower the usual cable into a position to be engaged with a load.

In Fig. I have illustrated a modified form of clutch which may be used in lieu of the clutch C above described. In such figure A designates the power shaft upon which are loosely mounted pinions K and K between which is located the clutch L splined by means of a feather Z upon the power shaft, as shown in Fig. 5. hen the shaft is rotated in the direction indicated by the arrow the engagement of the cam Z on the clutch member with the adjacent inclined surface on the hub of the pinion K moves the clutch member axially so that the tooth Z on the opposite side thereof will engage the tooth k on the hub of the pinion K thereby locking the pinion K to rotate with the shaft A. A rotation of the power shaft A in an opposite direction causes the pinion K to be locked to the shaft by reason of the clutch member being moved axially upon the shaft A owing to the cam surface on the hub of the pinion K engaging the adjacent cam surface on the clutch member L.

The operation of my improved hoisting mechanism is in all respects the same whether the form of clutch illustrated in Fig. 4 be employed or whether that illustrated in Figs. 1, 2, and 3 be used. It is therefore not necessary to further describe in detail the opera tion of the apparatus when the modified form of clutch shown in Fig. 4 is employed.

While I have shown a fly wheel as connected with the load lowering pinion to retard the rotation thereof and thereby effect an axial movement of the gear wheel E upon the hoisting shaft to apply the brake, yet it will be understood that I do not wish to limit myself to any specific means for this purpose as it is obvious that other devices may be employed without departing from the spirit of my invention. 1

From the foregoing description it will be observed that I have invented an improved hoisting mechanism by .means of which a load may be raised, lowered, or held at a fixed elevation, such result being accomplished by a power shaft, a hoisting shaft and interposed transmission gearing.

While I have describedmore or less precisely the details of construction, I do not wish to be understood as limiting myself thereto, as I contemplate changes in form, the proportion of parts, and the substitution of equivalents, as circumstances may suggest, or render expedient without departing from the spirit of my invention.

Having now fully described my invention, what I claim as new and desire to secure by Letters Patent is: i

1. In a transmission mechanism for hoists, the combination with a rotary power shaft, of a hoisting shaft, gearing inter osed between said shafts for rotating sai hoisting shaft in a direction to raise a load, gearing interposed between said shafts for rotating said hoisting shaft in an opposite direction, and means actuated by an initial rotation of said hoisting shaft in a direction to lower the load for locking said shaft against further rotation.

2. In a transmission mechanism for hoists, the combination with a rotary power shaft, of a hoisting shaft, gearing inter osed between said shafts for rotating saic hoisting shaftin a direction to raise a load, gearing interposed between saidv shafts for rotating said hoisting shaft in an opposite direction, means actuated by an initial rotation of said hoisting shaft in a direction to lower the load for locking said shaft against further rotation, and means for releasing said locking means actuated by an initial rotation of said power shaft in a direction to lower the load.

3. In a transmission mechanism for hoists, the combination with a rotary power shaft,

of a pair of pinions loosely surrounding said shaft, means for clutching one or the other of said pinions to said shaft according to its direction of rotation, a rotary hoisting shaft, a gear fixed upon said hoisting shaft in mesh with one of said pinions, a second gear wheel meshing with said second pinion and axially movable upon said hoisting shaft, a brake for preventing the rotation of the hoisting shaft in a direction to lower a load, means for actuating said brake by an axial movement of said second gear wheel, and means for locking said second gear wheel to said hoisting shaft after a sufficient axial movement thereof to release said brake.

4. In a transmission mechanism for hoists, the combination with a rotary power shaft, of a pair of pinions loosely surrounding said shaft, means for clutching one or the other of said pinions to said shaft according to its direction of rotation, a rotary hoisting shaft, a gear fixed upon said hoisting shaft in mesh with one of said pinions, a second gear wheel meshing with said second pinion and having an internally screw-threaded hub engaging a screw-thread on said hoisting shaft, a brake for controlling the rotation of said hoisting shaft, means for actuating said brake by the axial movement of said second gear wheel, and means for locking said second gear wheel to said hoisting shaft after a sufficient axial movement thereof to release said brake.

5. In a transmission mechanism for hoists, the combination with a rotary power shaft, of a pair of pinions loosely surrounding said shaft, means for clutching one or the other of said pinions to said shaft according to its direction of rotation, a rotary hoisting shaft, a gear fixed upon said hoisting shaft in mesh with one of said pinions, a second gear wheel meshing with said second ainion and axially movable upon said hoisting shaft, friction disks surrounding and rotating with said hoisting shaft, a relatively stationary cooperating friction disk, said friction disks being interposed between said first and second gear wheels and relatively moved axially by the axial movement of said second gear wheel.

6. In a transmission mechanism for hoists, the combination with a casing, of a rotary power shaft extending through said casing, a pair of pinions loosely surrounding said shaft, means for clutching one or the other of said pinions to said shaft according to the direction of its rotation, a rotary hoisting shaft, a gear wheel fixed upon said hoisting shaft in mesh with one of said pinions, a second gear wheel axially movable on said hoisting shaft and in mesh with said second pinion, a friction disk rotating with said hoisting shaft, a cooperating friction disk held from rotation through engagement with said casing, said disks being interposed between said first and second gear wheels and moved axially into engagement with each other by the axial movement of said second gear wheel, and means for locking said sec- 0nd gear wheel to said hoisting shaft after a sufficient axial movement thereof to release said brake.

7. In a transmission mechanism for hoists the combination with a rotary power shaft, of a pair of pinions loosely surrounding said shaft, means for clutching one or the other of said pinions to said shaft according to the direction of its rotation, a rotary hoisting shaft, a gear fixed upon said hoisting shaft in mesh with one of said pinions, a second gear wheel meshing with the other of said pinions and axially movable upon said hoisting shaft, a fly wheel secured to said second pinion, and a brake interposed between said gear wheels and actuated by the axial movement of said second gear wheel and means for locking said second gear wheel to said ,hoisting shaft after a sufficient axial movement thereof to release said. brake.

8. In a transmission mechanism for hoists, a hoisting shaft, a hoisting gear mounted on said shaft, a lowering gear mounted on said. shaft so as to have a limited movement thereon, a brake for said shaft arranged to be applied by the lowering gear when the gear approaches one limit of its movement on the shaft, means associated with said shaft and said lowering gear for locking them together when the gear approaches the other limit of its movement relative to the shaft, a pinion for driving each of said gears, a driving shaft, and connections between thedriving shaft and said pinions for effecting a driving engagement with one pinion or the other depending upon the direction of rotation of the driving shaft.

9. In a transmission mechanism for hoists, a hoisting shaft, a hoisting gear mounted on said shaft, a lowering gear mounted on said shaft so as to have a limited movement thereon, a brake for said shaft arranged to be applied by the lowering gear when the gear approaches one limit of its movement on the shaft, means associated with said shaft and said lowering gear for locking them together when the gear approaches the other limit of its movement relative to the shaft, a driving shaft, and means for effecting a driving connection with the driving shaft and the hoisting gear when the driving shaft is rotated in one direction and for effecting a driving connection between the driving shaft and the lowering gear when the driving shaft is rotated in the opposite direction at a speed equal to or greater than that which bears a predetermined relation to the speed of the lowering gear.

10. In a transmission mechanism for hoists, the combination with a rotary power shaft, of a hoisting shaft, gearing interposed between said shafts for rotating said hoisting shaft in a direction to raise a load, gearing interposed between said shafts for rotating said hoisting shaft in an opposite direction, means for locking said hoisting shaft against rotation actuated by an initial rotation of the hoisting shaft in the direction to lower the load and by a rotation of the hoisting shaft in the lowering direction at a greater speed than that produced by the power shaft, and means for releasing said locking means actuated by an initial rotation of said power shaft in a direction to lower the load.

In testimony whereof, I sign this speci-' fication in the presence of two witnesses.

ARTHUR J. THOMAS.

Witnesses:

GEO. L. WILKINSON, RUBY NASH. 

